Bumper for motor vehicles



May 19, 1925.

G. F. KOLB BUMPER FOR MOTOR VEHICLES 3 Sheets-fSheet 1 May 19, 1925:1,538,190

` G. F. KOLB BUMPER FOR MOTOR VEHICLES 'F;'&led May s. 1923 I5Sheets-Sheet 2 l y IN V EN TOR /7 a 7e 0% Z/ BY f4 ik@ @nl faz/4, vATToRA/gl/K 1,538,190 G. F. KOLB BUMPER FOR MOTOR VEHICLES Filed May 8'.1923 3 Sheets-Sheet 3 May 19, 1925.'

Patented May 19, 1925.

'UNITED STATES PATENT OFFICE.

GEORGE F. KOLB, F FAIRFIELD, CONNECTICUT,'ASSIGNOR TO THE BULLARD MA-CHINE TOOL CO., 0F BRIDGEPORT, CONNECTICUT, A CORPORATION OF CONNECTI-CUT.

BUMPER FOR MOTOR VEHICLES.

v Application led May 8,

new and useful Improvements in Bumpers for Motor Vehicles, of which thefollowing is a specification.

My invention relates to motor vehicle bumpers.

A principal object of the invention is to provide a bumper of very lightweight, which is at the same time unusually strong and durable, providesample yielding resistance to impacts, and which may be manufactured atlow cost.

Another important object is to provide a bumper which realizes some orall of the foregoing objects, and in which the outer or in'lpact'memberis of ample width in the vertical direction, to insure properengagementwith the bumpers or other p-arts of motor vehicles or otherobstacles, so that the liability of over-lapping and consequent damageto the vehicle on which the present bumpers are placed, is very largelyor entirely eliminated;

Another object is to provide a bumper which has, by reason of itsstructural features, a distinctive and attractive or decorativeappearance.

To attain the foregoing and other objects, l provide an impact member orfront bar, which may be ot stamped or pressed sheet metal, and which isin general of channel section, with `an outerface of ample width in thevertical direction and usually provided with a plurality of openings forthe sake of lightness and decorative appearance, and which has upper andlower flanges of ample width to provide substantial stiffness inhorizontal planes, and independent spring supports, each of whichpreferably consists of a single piece of flat spring meta-l. Thesesprings or supporting members have important novel characteristicssuliiciently explained in the detail description.

The construction is such that pressure directed against the impactmember near one end thereof, is yieldingly absorbed, mainly by one ofthe spring supports, `and pressure or shocks directed against the impactmember near the center thereof, are yielding-ly absorbed by both of thespring supports.

1923. serial No. 637,543.

The impact member may move towards the vehicle several inches, andtheresistance afforded to the movement of the impact member increases.rapidly in proportion to the lamount of its deflection. Very heavyshocks or impacts are thus absorbed without damage to the bumperstructure or the vehicle.

The characteristics and advantages of the invention are furthersufficiently described in connection with the following detaildescription lof the accompanying drawings, which show certainexemplifying embodiments. After considering these, persons skilled inthe art will understand that many variations may be made within theprinciples of the invention; and I contemplate the employment of anystructures that are properly within the scope of the appended claims.

Figure l is a plan view of ar bumper, embodying the invention in oneform, in position on the front end of a motor vehicle.

Figure 2 .is a front elevation of the same.

Figure 3 is a left end elevation.

Figure t is a section at f-e, Figure 2.

Figure 5 is a section at 5--5, Figure 2.

vFigure 6 is a section at 6-6, Figure l.

Figure 7 is a sect-ion at 7-7, Figure 2.

Figure 8 is a top plan of the impact bar and Figure 9 is a frontelevation of the same, illustrating a modilication includingreinforcements associated with the bumper bar.

Figure l() is a section at lO--l0, Figure 9, e

showing a connection device adapted for the reinforced structure ofFigures Sand 9.

Referring lirst to the embodiment of the invention shown in Figures l to7 The impact member 12, which may otherwise be identified as the bumperbar or impact bar, may vary considerably in detail, but desirably, inone form of the invention, as here shown, it is moderately curved asviewed in plan, Figure l, the convex curvature being directed forwardlyor away from the vehicle. The front face 13 of the impact bar desirablyhas, as shown, very substantial vertical depth so that when the impactmember encounters another bumper, another Vehicle, or any otherobstruction, it does not easily overlap, or pass above or below theobstruction. ln other words, it almost cerlGO tainly encounters aprojecting part of the obstacle and` prevents direct contact of theobstacle with the vehicle on which the bumper is placed.

For the sake of lightness and manufactur ing economy, the impact memberis desir-- ably stamped or pressed from sheet metal, and when properlydesigned, even though the material is relatively thin, it hasV amplestrength and rigidity7 to resist permanent bending under even very heavyblows, although it has a certain amount of resiliency which enables itto yield within its limit of elasticity, without taking a permanent Set.To strengthen and stillen the bar, top and bottom webs or lflanges llland are provided, of substantial width, so that the vgeneral crosssectional form of the impact bar, (Figure el) is that of a channel orC-bea'm.

Desirably, for the sake of lightness and decorative appearance, the-front face or web 13, is formedwith a plurality of openings 1G, whichmay vary in shape and arrangement to give different desired decorativeeffects. ln the present specific example, these openings are ofgenerally oblong forni with rounded corners, and the metal of the frontweb 13 is bent or pressed in about each opening to provide a` shallowflange 17. These flanges materially stillen and strengthen the barwithout adding appreciably to its weight. The ends of the front web 13are desirably curved slightly inward or rearward as at 1S, Figures 1 andfll, and the top and bottom flanges are desirably cut near their ends ondiagonal lines, as at 19, to avoid any sharp outer corners.

ln a large number of bumpers now in use., the front 'or impact membersconsist 'of parts of the spring bars. Then any considerable verticalsurface is provided in bumpers of Jthis class, it is, therefore,necessary to provide two or more vertically superposed spring bars inthe front face of the bumper, which materially increases the viieightand cost of the structure. lt is, moreover, diflllicult to properlyfinish these spring members, since they cannot be conveniently handlediu`any economical way in the necessary grinding or polishing operations..My invention does away with these difficulties by `providing aone-piece front member or impact bar of ample vertical` width, but ofthi-n cross section and light in weight, while approximately orsubstantially rigid under ordinary conditions, and this single piece ofmetal can be easily handled in grinding and polishing operations vtoprovide a smoothlinished front face, which may then be nickel-plated togive the desired linish to the front of the bumper. It is customary toenamel or paint most or all parts of the bumper structure, except 'thefront face of the impact member proper, and the described inipact memberconstruction materially simpliies and cheapens the most expensivefinishing operation.

The formation of the bumper bar as described provides a plurality ofspaced vertical webs or web-members and 21, each of shallow channelsection, connecting the long upper and lower front members or webs 22and 23, which are of channel section at points intermediate the verticalmembers 20 and 21, as sulliciently shown in Figure 5, all the parts ofthe impact bar being, ol" course, integral, in the preferred mode ofconstruction.

In a great number of bumpers now in use, and especially most of those inwhich the cushioning el'lect is provided by strips of flat spring metal,these spring' strips are continuous from one rside lof the vehicle tothe other, and they form in themselves the impact member or members, orelse the impact member is a piece of flat metal secured to thecontinuous spring strips and having in itself no considerable strengthor resistance to bending strains. The long, continuous spring strips areunduly heavy and expensive and when a separate front plate of thecharacter just described is connected to them the appearance of thestructure is frequently awkward and unsightly. To avoid thesediliiculties vand disadvantages, I provide, in connection with theimpact member above described, relatively short, light, 'andinexpensive, independent spring supports, each consisting of a strip offlat spring metal bent to a suitable shape to provide the necessaryvertical stiffness for the proper support of the impact member, and thenecessary spring resistance to impacts in the horizontal, longitudinaland lateral directions, one of these spring supports being provided foreach end portion of the bumper bar.

Specilically, in a preferred construction, as shown in the drawings,cach spring support consists of a strip 25 of flat spring steel bent toform a single outer loop QG, and a double or S-shaped inner loop 27,including a loop or bend 28 close to the vehicle frame and another loopor bend 29, relatively near the bumper bar, the bends 2S and 29 usual-lybeing connected by a substantially straight portion 30, although theshape of the S-loop 27 may be varied considerably. Adjacent to the 'bend28 is 'a spring portion 31, which is usually straight and arranged in atransverse plane of the vehicle. This single straight portion of thespring support is connected to the vehicle side frame 82 by any suitablebracket. The .provision of a single flat member 31 of the spring supportat a point adjacent to the vehicle frame, however, permits the use of animproved bracket of a simple and cheap construction, which is moreover,very easily and economically attached to the vehicle.

The bracket, therefore, in a preferred embodiment of the invention, mayconsist of a piece of pressed or stamped sheet metal including asubstantially fiat, curved member 35, the curvature of this memberconforming to the curvature o' the frame member 32, which is in thepresent instance the front end ot a side frame member, or spring horn.When the bumper is to be attached to the rear end of the vehicle, thebracket or the bracket member 85 may be suitably modified for connectionto any suitable part of the rear frame structure of thevvehicle. ln thepresent example, where the bracket is connectedL to a front spring horn,the member has an enlarged portion 36, provided with an aperture at 37to accommodate the spring bolt, which passes through the :front end ofthe spring horn; and the member 35 is secured to the trame member 32 byone, or preferably at least two bolts 3S. At its forward end the member35 is bent angularly to provide a clamp member 38 and this portion ofthe bracket sheet is then'bent substantially in U-form to provide aclamp member 39. The clamp strueture so produced may be slitfened by aweb or corner member 40, bent over in the horizontal plane as mostclearly shown in Fig ure l, and this member may be, in some cases,arranged to rest on the upper surface oit the 'front end of the springhorn and support the bracket, in addition to the support provided by itsbolt kconnections 38, and aperture 37 fitting around the spring bolt.

The single, straight member 31 of the spring support passes between theclamp members 3S and 39 and is secured by a bolt 4l passing throughsuitable holes in the lower ends of the clamping members.

Extending inwardly from the outer bend 26 of the spring support is aportion 45 ot the spring strip curved in substantial con* 'ifm'mity tothe curvature of the bun'iper bar, and lying against the inner surfaceof the veri ical web 11 9, or more particularly against the inner edgesof flanges li' of the apertures therein. rllhis portion of the springmember may be secured to the bumper bar at one or more points. @ne pointof connection, desir-ably, is substantially at the vertical web member2O between two .of the end openings 1G, that is to say, at a pointconsiderably .inward from the end of theI Vbumper bar. The form oitconnection at this point may vary considerably but in a preferredembodiment, as sho-wn, it includes a strip 46a of ibre or other suitablemore or less eompressible material (Figure 6), arranged vern 'tically inlthe channel member 20 just reterred to and serving substantially as afiller to form a supporting surface for the spring member,sul'istantially flush with the edges oi the adjacent shallow webmen'ibers 17. The spring member 45 lies against the inward face of strip46 and the inner edges of the adjacent flange members 1T, and is securedby a clip 46, usually ot pressed sheet metal, having shoulders 4?engaging upper and lower edges ot' the spring member to prevent verticaldisplacement of the bumper bar. The clip is secured in position by bolts4S passing through suitable holes in the ends of clip46 and in the fibrestrip 4Ga and bumper member 20, and desirably, the bolt heads 49 arerelatively flat and thin and are arranged outwardly, that is, so thatthese thin bolt heads appear on the front face of the bumper bar, wherethey are relatively unnoticeable; and they are usu ally nickel-plated,and then contribute to the highly finished and decorative appear ance ofthe front bumper surface. In this way the spring member 45 is heldsecurely in position against a compressible washer or strip 46, whichprevents loosening of the connection, squeaking or rattling, and also itpositively prevents vertical displacement of the impact bar. ln somecases `the spring member 45 may be eut ofii' at a point just inward fromclip 46, but desirably, it con-- tinues along the inner face of thebumper bar to a point 50.

The portion 5l of spring support Q5 ci;- tending forward and inward frombend 29 is formed with a moderate curvature, substantially greater thanthe curvature of the bumper bar and spring portion 45, the eonveXity ofthis curved portion 5l being directed forwardly, and the end of springmember 51 is usually located in line with the other end of springportion45. The twoV spring ends are connected together and to the bumperbar by a bolt 53 (Figure 7) passing through the two spring ends 50 and52, and through vertical bumper web member 2l, these bolts 53 beingsubstantially similar to bolts 48 and. arranged in a similar way with'their flat heads 54 outward. Desirably, a strip or washer 55 of fibreor other suitable, more or less compressible material, is located` inthe channel portion of the bumper bar defined by the edges of theadjacent flange members 17, and the flat outer face ot spring member 45rests against the washer, which is compressed by bolt 58, and againstthe edges of the flanges 17.

The portion of each spring support between its member 3l and the outerbend 26 may be variously formed, but desirably, this portion 60 iscurved on a moderate arc with the convexity directed forwardly, toincrease the spring effect and also to provide added cleaance betweenthe spring support and the vehicle whe-el, which is sufficientlyindicated in dotted lines at Gl.

The described spring supports with their connections to the vehicleframe and to the bumper bar support the latter practically CIJ llt)

lll

rigidly in the vertical direction, but provide ample flexibility inhorizontal planes, longitudinally of the vehicle and also laterally, toa sufficient extent to take up shocks directed against the bumper bar inpractically any possible direction. An impact against the bumper barnear one of its ends is taken up mainly by the spring support at thatside of the vehicle. The curved portion 6() yields rearwardly while thebend 2G is shortened, and the bends 28 and 29 of the S-loop are alsocompressed oi' shortened, while the curved meinbei' 5l yields with aprogressively increasing resistance. The arrangement of the curvedmember l is such that it is normally spaced away from the adj acentspring member from a point just outward from the point of connection atthe bolt 53, and this clearance increases progressively toward the bend29. `When the bar is deflected rearwardly, curved member 5l flattensout, and the point of resistance is thus transferred progressively fromthe point near the bolts 53 to point near the bend 29. The spring,adjacent to the member 5l, is, in other words, shortened, giving aprogressively stiffening spring resistance to the shock. In the case ofa very heavy shock the spring support may yield backwardly until thebend 29 is substantially in contact with the bumper bar and also isclose to or in contact with the spring member 3l. A very considerablerange of longitudinal deflection is thus provided for, sufficient toabsorb very heavy shocks without injury to the bumper or to the vehiclewhich carries it.

When the impact is directed toward the center of the bumper bar, both ofthe spring supports are deflected simultaneously with a` progressivelyincreasing resistance, in a manner which is sufficiently clear from thepreceding description ofv the action of one of the springs.

In some cases it is desirable to additionally reinforce the centralportion of the bumper bar, and the reinforcement may also be extendedsubstantially to the ends of the bar. Figures S to l0 suflicientlyillustrate such reinforcements, in one preferred forni. Thereinforcements in this instance consist of upper and lower round rodsand 7l of suitable metal, such as ordinary or spring steel. These rodsare located in the channels provided by the upper and lower flanges 14and l5 and the adjacent shallow flanges 17 at the rear or inner face ofthe bumper bar. The rods ina-y be welded or otherwise secure'd in placein variousways. Usually it is not necessary to connect them j)erinaiiently or integrally to the bumper bar. Desirably, in oneprefeired construction, they may be held in place by the clips or otherfastening devices which secure the bumper bar to the spring` support.Figure l() sufiiciently shows one preferred mode of connecting thereinforcing rods in position. In this arrangement, one of theconnections such as the clip 46 of Figure 6, is modified by providing`end extensions which are curved to engage or substantially fit the rods7() and 71, and have end portions 76 overlying the rearward sides orfaces of the rods, so that the rods are securely held in place when theclips are tightened to hold the spring members 45, or other springmembers which may be secured by the clips at the different connectionpoints. The described construction is such that the reinforcing rods maybe incorporated in the structure whenever that is desirable, for anyparticular service, or they may be omitted, without affecting at all, orto any considerable extent, the other features of the structure.

I claim:

l. In a vehicle bumper, an impact bar of pressed sheet metal, of alength sufficient to span the front end of a motor-vehicle, having avertically wide front web, and having wide rearwardly-directed top andbottom flanges, the front web having spaced apertures, with shallow,rearwardly-directed flanges around their edges, and independent springsupports, each consisting of a single strip of flat spring-metal formedwith a single outer bend and an inner S-bend, and with its ends kbroughttogether and secured against the inner face of said front web of theimpact bar at a point substantially outside tlie center line of thevehicle, portions of the two springi supports between their single andS-bends being adapted to be secured to brackets or frame members of thevehicle near the opposite sides thereof.

2. A bumper for vehicles comprising, an impact bar of substantiallyrigid construction, and independent spring supports for the two ends ofthe impact bar, each spring support consisting of a single strip of fiatspring metal bent to form a single outer bend and an inner S-bend withan intermediate member arranged for connection lo a bracket on a vehicleframe member .near one side of the vehicle, an end portion of the springstrip extending inward from the outer bend and secured to the impact barat a point considerably inward from the adjacent end thereof, the otherend portion of the spring strip extending inwardly from the forwardportion of the S-bend and curved convexly in a forward direction and theend of said portion being` secured to the impact member at a pointsomewhat outward from the longitudinal center line of the vehicle.

3. A bumper for vehicles comprising, an impact bar of integral andcomparatively rigid construction, and independent spring supports forthe two ends ofthe impact bar, each spring support consisting of asingle stiip of flat spring metal bent to form a- Cfr single outer bendand an inner S-bend with a single substantially straight portion betweenthe bends arranged in the vertical transverse plane of the vehicle towhich the bumper is attached,u said straight portion being adapted forconnection to a bracket on a. vehicle frame member near one side of thevehicle, an end portion of the spring strip extending inward from theouter bend being secured to the impact member at a point considerablyinward from the adjacent end thereof, the other end portion of thespring strip extending inwardly from the forward portion of the S-bent,being curved convexly in a forward direction and the end of said portionbeing secured to the impact member at a point outward from thelongitudinal center line of the vehicle.

1l. A bumper for motor vehicles comprising, an impact bar of integralpressed sheet metal in general of channel cross section, having a widefront face or web in the vertical direction and having wide top andbottom flanges rearwardly7 directed, and individual spring supports, onelocated near each end of the impact bar, each spring support consistingof a strip of flat spring metal, the two ends of which are connectedtogether and to the vertical web of the impact member at a point outwardfrom the longitudinal center line of the vehicle, one portion of thespring strip adjacent to one of its ends being curved rearwardly to agreater degree than the curvature of the impact member to provide aprogressively stiftening spring resistance to impacts, the springsupport also having a single outward bend and an inward S-bend, saidbends bcing connected by a substantially straight single stretch of thespring member, arranged in a vertical transverse plane of the vehicleand adapted to be secured to a bracket attached to a vehicle :framemember.

ifi bumper for motor vehicles compris ing, an impact bar of .integralpressed sheet metal in general of 'channel cross section, having a widefrontface or web in the vertical direction and haviiig wide top andbottom flanges rearwardly-directed, and individual spring supports, onelocated near each end of the impact bar, each spring support consistingof a strip of tlat spring metal, one end of which is connected lo thevertical web of the impact member at a point outward from theloiugitndinal center line of the vehicle, a portion of the spring stripadjacent to said end being curved rearwardly to a greater degree thanthe curvature of the impact member to provide a progressively stitfeningspring resistance to impacts, another end portion of the spring stripextending along' the inner face of the vertical web of the impact barand being connected thereto at a point between the aforesaid connectionand the end of the bar, the sprin Y support also having a single outwardbend and an inward S-bend, said bends being connected by a substantiallystraight single stretch of the spring member, arranged in a verticaltransverse plane of the vehicle and adapted to be securedrto a bracketon a vehicle frame member.

6. A bumper for vehicles comprising, an impact bar of substantiallyrigid construction, and independent spring supports for the two ends ofthe impact bar each spring support consisting of a singlestrip of tiatspring metal bent to form a single outer bend and an inner S-bend withan intermediate member arranged for connection to a bracket on a vehicleframe member near one side of the vehicle, an end portion of thespringstrip extending inward from the outer bend and secured to theimpact bar at a point considerably inward from the adjacent end thereof,the other end portion of the spring strip extending inwardly from theforward portion of the S-bend and curved convexly in a forward directionand the end of said portion being secured to the impact member at apoint somewhat outward from the longitudinal center line of the vehicle,the devices for securing the spring supports to the impact bar eachincluding a filler strip located between a spring member and the bar,and clamping means securing a spring member against the compressiblemember and to the impactmember.

7. A bumper for vehicles comprising, an impact bar of substantiallyrigid construction, and independent spring supports for the two ends ofthe impact bar each spring support consisting of a single strip of 'flatspring metal bent to form a single outer bend and an inner S-bend withan interme diate member arranged for connection to a bracket on avehicle frame member near one side of the vehicle, an end portion of thespring strip extending inward from the outer bend and secured to theimpact bar' at a point considerably inward from the adjacent endthereof, the other end portion of the spring strip extending inwardlyfrom the forward portion of the S-bend and curved convexly in a forwarddirection and the end of said porti m being secured to. the impactmember at a point son'iewhat ont ward from the longitudinal center lineof the vehicle, the devices tor securing the spring supports to theimpact member including tiller strips of compressible material locatedbetween the spring members and t-he vertical web of the impact bar,clips including portions securing spring members against` the tillerstrips and to the impact bar, and means for clamping the clips to thebar. y

8a A connection for rector vehicle bumper members comprising, an impactbar of generally channel cross section having openings in its verticalweb, the adjacent ends of these openings being defined by vertical webportions having parallel sides formed by shallow inturned flanges of thewebmaterial, a substantially flat longitudinal spring strip lyingparallel to the vertical web of the impact bar, a filler strip lyingagainst one of said vertical web portions between the spring member andsaid web and also between said shallow web flanges, a. clip straddlingthe spring member and having ends extending above and below said member,and bo-lts passing through the clip ends and securing the clip, springmember', and filler strip in fixed relation to the web of the impactbar.

9. A connection for motor vehicle bumper members comprising, an impactbar of generally channel cross section having openings in its verticalweb, the adjacent ends of these openings being defined by vertical webportions having parallel sides formed by shallow inturned flanges of theweb material, a substantially flat longitudinal spring strip lyingparallelv to the vertical web of the impact bar, a strip: ofcompressible material lying against one of said vertical web portionsbetween the spring member and said web and also between said shallow webflanges, a clip straddling vthe spring member and having ends extendingabove and below said member, and bolts passing th-rough the clip endsand securing the clip, spring member and strip of compressible materialin tixed relation to the web of the impact bar.

l0. A motor vehicle bumper comprising, a bumper bar of pressed sheetmetal and of generally channel cross Section, and one or morelongitudinal reinforcing rods at the rear side of the bumper bar.

l1. A motor vehicle bumper comprising, a

bumper bar of pressed sheet metal and of generally channel crosssection, and one or more longitudinal reinforcing rods at the rear sideof the bumper bar, spring supports adapted to be secured to framemembers' of a vehicle, means for securing the spring supports to thebumper bar, said means including clips adapted to engage said springsupports, said clips having members adapted to engage and retain thereinforcing rods in position at the rear of the bumper bar, and meanssecuring the clips to the bumper bar.

12. Ainotor vehicle bumper comprising, a bumper bar of pressed sheetmetal and of generally channel cross section, and having longitudinal,upper and lower channel forinations in its' rear tace, and reinforcingrods secured in said longitudinal channel formations'.

13. A motor vehicle bumper comprising, a bumper bar of pressed sheetmetal and of generally channel cross section, and having longitudinal,upper and lower channel formations in its rear face, and reinforcingrods secured in said longitudinal channel formations, spring supportsadapted to `be secured to frame members' of a vehicle, means forsecuring the spring supports to the bumper bar, said means includingclips adapted to engage said spring supports, said clips having membersadapted to engage and retain the reinforcing rods in position, and boltsfor securing the clips to the bumper bar.

Signed at Bridgeport in the county ot' Fairfield and State ofConnecticut, this 18th day of April A. D. 1923.

GEORGE lf. KOLB.

lVitnesscs A. E. Non'rrr, E. O. BLANCHARD.

